Wave Energy technology produces both clean water and clean energy

Instead of generating electricity at sea and sending it to shore, a different kind of wave energy device is in the works in Australia, and it promises to deliver not only emissions-free electricity, but also emissions-free desalinated water.

The technology, called CETO after a Greek sea goddess, is being developed by Carnegie Wave Energy Limited, and their upcoming 2MW pilot project near the Perth Wave Energy demo site will be the first wave powered desalination plant in world.

"The CETO system is different from other wave energy devices because it operates under water and is anchored to the ocean floor. Several fully submerged buoys are tethered to seabed pump units. The buoys move with the motion of the passing waves and drive pumps. The pumps pressurise water which is delivered on shore via an underwater pipe. On the shore, high-pressure water is used to drive hydroelectric turbines, generating zero-emission electricity. The high-pressure water can also be used to supply a reverse osmosis desalination plant, replacing or reducing the reliance on greenhouse gas-emitting, electrically-driven pumps usually required for such plants." - Carnegie Wave Energy

The CETO system is said to be environmentally friendly, with minimal visual impact due to its submerged design, which will also keep it from being affected by storms or breaking waves. Multiple units can be joined into a single array, making it modular and scalable up to the appropriate size for any project.

According to the company, the system is "the most efficient and cost effective way to desalinate freshwater from wave energy," because it doesn't need to send electricity to shore and then convert it into mechanical energy for pumping, which would involve losses in efficiency and additional costs for equipment and maintenance (the transmission and pumping equipment).